7. Insertion

The location and angles at which each mini implant is inserted determine the position of its head (for attachment purposes) and should also be planned to maximise the bone quantity around the body. In particular, since the average periodontal ligament width is 0.25mm then it is desirable to have 1mm clearance around threads.

The mini implant may be inserted using either manual long or mini screwdrivers, or mechanically using a screwdriver mini insert in a contra-angle handpiece. The standard screwdriver (DB10-0021) is used for most buccal insertions, whilst the mini screwdriver (DB10-0025) or mini screwdriver insert (DB10-0026) used in a speed reduction handpiece is more useful in the retromolar regions, in the mid-palate, and in the posterior palatal alveolus. The principles are similar as follows:

A) Break the seal of the packaging, if sterile remove plastic cap. If non-sterile the implant must be sterilised in the aluminium Infinitas tray before proceeding. Using light pressure lock the screwdriver securely onto the head of the Infinitas mini implant.

B) The tip of the mini implant is placed onto the mucosa (if present) or exposed cortical surface at the desired position and 3D orientation. If a stent is used then this positional information will be dictated by the engagement of the screwdriver within the guidance cylinder. The mini implant is slowly inserted by rotating the screwdriver handle clockwise with one’s fingers and with firm seating pressure at the base of the handle. It’s essential that one’s wrist is stabilised and that the rotations are produced by didgit movements only. If the mini screwdriver is used, the handle is twisted clockwise with firm seating pressure applied with the contralateral forefinger. Firm pressure is used to penetrate the cortical plate, but once resistance lessens then the mini implant should be inserted primarily by rotational means.

C) As the mini implant is gradually advanced through cancellous bone then the resistance/torque felt by the clinician will most likely begin to increase, especially in the mandible. Excessive resistance may result in either implant fracture or bone necrosis. In such circumstance the insertion should either be paused for 10 to 20 seconds (this allows the viscoelastic bone to expand around the mini implant), or the mini implant should be unscrewed by 1 to 2 anticlockwise turns before inserting it further as normal. These measures may be repeated as often as necessary.
When a speed reduction contra angle handpiece is used care should be taken not to exceed approximately 60 RPM, to avoid bone necrosis. The Infinitas mini implant should be inserted until the top of its body firmly engages the cortical plate and/or the head is at the desired level of projection. Notably, if primary stability is unsatisfactory then the mini implant should be removed and the insertion process repeated at a different site. Also, it may be useful to take a radiograph to check the mini implant position in relation to adjacent structures, and re-position it if necessary